Accept --manifest-path (#168)

NEWS.md

@@ -8,6 +8,8 @@
 
 - Added: Alternative aliases for command line options, so you don't need to remember if it's "regex" or "re": `--regex`, `--examine-re`, `--examine-regex` (all for names to include) and `--exclude-regex`.
 
+- Added: Accept `--manifest-path` as an alternative to `-d`, for consistency with other cargo commands.
+
 ## 23.11.1
 
 - New `--in-diff FILE` option tests only mutants that are in the diff from the

src/main.rs

@@ -33,6 +33,7 @@ use std::fs::read_to_string;
 use std::io;
 use std::process::exit;
 
+use anyhow::ensure;
 use anyhow::Context;
 use anyhow::Result;
 use camino::Utf8Path;
@@ -156,6 +157,10 @@ struct Args {
     #[arg(long)]
     list_files: bool,
 
+    /// path to Cargo.toml for the package to mutate.
+    #[arg(long)]
+    manifest_path: Option<Utf8PathBuf>,
+
     /// don't read .cargo/mutants.toml.
     #[arg(long)]
     no_config: bool,
@@ -240,10 +245,19 @@ fn main() -> Result<()> {
     console.setup_global_trace(args.level)?;
     interrupt::install_handler();
 
-    let start_dir: &Utf8Path = args.dir.as_deref().unwrap_or(Utf8Path::new("."));
+    let start_dir: &Utf8Path = if let Some(manifest_path) = &args.manifest_path {
+        ensure!(manifest_path.is_file(), "Manifest path is not a file");
+        ensure!(
+            args.dir.is_none(),
+            "--dir and --manifest-path are mutually exclusive"
+        );
+        manifest_path.parent().expect("Manifest path has no parent")
+    } else if let Some(dir) = &args.dir {
+        dir
+    } else {
+        Utf8Path::new(".")
+    };
     let workspace = Workspace::open(start_dir)?;
-    // let discovered_workspace = discover_packages(start_dir, false, &args.mutate_packages)?;
-    // let workspace_dir = &discovered_workspace.workspace_dir;
     let config = if args.no_config {
         config::Config::default()
     } else {

src/workspace.rs

@@ -107,16 +107,18 @@ struct PackageTop {
 }
 
 impl Workspace {
+    /// Open the workspace containing a given directory.
     pub fn open<P: AsRef<Utf8Path>>(start_dir: P) -> Result<Self> {
         let dir = locate_project(start_dir.as_ref(), true)?;
-        let cargo_toml_path = dir.join("Cargo.toml");
-        debug!(?cargo_toml_path, ?dir, "Find root files");
+        let manifest_path = dir.join("Cargo.toml");
+        debug!(?manifest_path, ?dir, "Find root files");
         check_interrupted()?;
         let metadata = cargo_metadata::MetadataCommand::new()
             .no_deps()
-            .manifest_path(&cargo_toml_path)
+            .manifest_path(&manifest_path)
             .exec()
-            .context("run cargo metadata")?;
+            .with_context(|| format!("Failed to run cargo metadata on {:?}", manifest_path))?;
+        debug!(workspace_root = ?metadata.workspace_root, "Found workspace root");
         Ok(Workspace { dir, metadata })
     }
 

tests/cli/workspace.rs

@@ -10,6 +10,24 @@ use serde_json::json;
 
 use super::{assert_bytes_eq_json, copy_of_testdata, run};
 
+#[test]
+fn open_by_manifest_path() {
+    run()
+        .args([
+            "mutants",
+            "--list",
+            "--manifest-path",
+            "testdata/factorial/Cargo.toml",
+        ])
+        .assert()
+        .success()
+        .stdout(indoc! {"
+            src/bin/factorial.rs:1: replace main with ()
+            src/bin/factorial.rs:7: replace factorial -> u32 with 0
+            src/bin/factorial.rs:7: replace factorial -> u32 with 1
+        "});
+}
+
 #[test]
 fn list_warns_about_unmatched_packages() {
     run()